Klokočník, Jaroslav - Kostelecký, J.
Lowest degree and order harmonic geopotential coefficients and their possible time variations from analysis of geostationary orbits in frame of COGEOS.
COGEOS: a colletion of papers. Pisa: Pisa University, Zaragoza University, 1993, s. -
http://hdl.handle.net/11104/0021897